Steering-gear mechanism



April 15, 1930. E. s. M PHE'RsoN STEERING GEAR MECHANISM Filed March 14. 1927 2 Sheets-Sheet l April 15, 1930. s, acp so 1,754,632

STEERING GEAR MECHANISM Filed March 14, 1927 2 Sheets-Sheet 2 v awuento'c Patented Apr. 15, 1930 l 1 srarss rrsur OFICE EARLE S. MACPHERSON, OF DETROIT, MICHIu-AN, ASSIGNOR 'I'O HUPP MOTOR CAR CORPORATION, OF DETROIT, MICHIGAN, A CORPORATION OF VIRGINIA STEERING-GEAR MECHANISM Application filed March 14, 1927. Serial No. 175,360.

This invention relates to a steering gear is illustrated a front axle 10 within the forked mechanism and more especially to a steering ends 11 of which steering knuckles 12 are mechanism for use in connection with motor mounted, which knuckles carry the usual vehicles and the like. wheel spindles 13 upon which steered ground One of the principal objects of this invenengaging wheels (indicated by dotted lines) 55 tiontion is to provide simple but efi'ective are adapted to be mounted. means for eliminating the shimmying of the The reference character 14 indicates a Wheels and in accordance with the present Worm shaft provided with a Worm 15. This invention this object is accomplished by an shaft constitutes the driving member and arrangement which acts to destroy synchroadapted to be rotated, during the steering re nism between the steered ground engaging of the vehicle,by means ofasteering wheel 16. wheels. Pivotally mounted upon a shaft 17, which is To obtain the above mentioned advantages vertically supported by means of a bracket it is proposed to provide each of the pair of 18, is a pair of driven members 19, entirely steered road wheels with a driven actuating independent of one another. These driven 65 member entirely independent of the other members 19 are provided with lateral prod t id an actuated by the steering jections 20 which engage the worm 15 on dih l h i d i i g connection with these ametrically opposed sides thereof so that the two independent actuating means. Inasmuch members 19 are oscillated upon a rotation of as the connection between the driving and vorm 15. Connected to each driven member 70 driven members includes a reduction gear- 19, for oscillation therewith about shaft 17, ing and this reduction gearing constitutes the is an arm 21, each of which is connected to a sole connection between the driven members, steering knuckle 12 by means of a rod 22 pivit is impossible for the wiggle or shimmying otally connected as at 23 t0 the said arm, and of one of the steered road Wheels to be transas at 2-1 to a steering arm 25 projecting from 7 mitted to the other because of the friction the steering knuckle. It will be observed that and irreversibility of the reduction gearing. the members 19 and 21 constitute bell cranks Furthermore the motion of one of the ground by which motion may be transmitted from engaging wheels which might occur by reason the worm 15 to the links 22 for operating the of the clearance which exists between its steering knuckles. so driven member and the driving member of the In the construction shown in Figure 2 steering mechanism, cannot be transmitted the worm 26, which constitutes the driven to the other ground engaging wheel withmember, is rotated by means of steering wheel out acting through the irreversible reduction 27 and actuates a pair of independent driven gearing and as a consequence the transmismembers 28 similar in construction to the as sion of such movements is so adequately repreviously described driven members 19. One sisted as to prevent its occurrence. of these members is carried by shaft 29 which Other objects and advantages and the novel ext-ends loosely through a sleeve 30 which cardetails of construction of two embodiments of ries the other member 28. Levers 31 and it) the invention will be made more apparent as are secured respectively to the shaft 29 and as this description proceeds, especially when sleeve 30. Lever 31 is connected by means of considered in connection with the accompanya rod 33 to the steering arm 34 projecting ing drawings, wherein: from the steering knuckle 12. The other Figure 1 is a perspective view of a steering lever 32 is connected by a rod 35 to a lever 36 a gear constructed in accordance with this inpivotally mounted upon the axle l0 and con- 95 vention, and nected through its pivot to a second lever 37 Figure 2 is a similar view of a slightly which in turn is connected byaconnectingipd modified form of construction. 38 to the steering arm 34 of the other steer Referring now more particularly to Figure ing knuckle. l of the drawings it will be noted that there In both of the herein described forms of the H10 invention it will be noted that a rotation of the driven member, that is, the worm 15 in Figure 1 and the worm 26 in Figure 2 causes an oscillation of the driven members which are the actuating means for the two steered ground engaging wheels whereupon these wheels may be moved, as customary, during steering. However, it will be noted that in both forms of the invention, each of the steered ground engaging wheels, has an actuating means separate from and independent of the actuating means of the other steered wheel and that the sole connection between the actuating mean of the pair of steered wheels is the driven member, herein illustrated as a worm, actuated by the steering wheel. Furthermore the driving and driven elements constitute a reduction gearing which is inherently irreversible. As a con sequence of this construction one of the ground engaging wheels cannot transmit motion to the other even to the extent of the clearance of back lash which exists between the driven members and the worm, without rotating the worm, which is impossible, or practically so. Thus the clearance which exists between each of the driven members and the worm, which may be the result of the original design or of wear occasioned thereto and which will permit either or both of the wheels to wiggle or shimmy through an angle depending upon the extent of such clearance, cannot be transmitted directly to the other ground engaging wheel. Therefore, all directconnection between the steered and ground engaging wheels is eliminated and a more efficient and satisfactory steering gear mechanism produced.

It should be understood that the two forms of the invention illustrated and described herein, somewhat in detail are for the purpose of illustration only and should not be construed as in anywise limiting the invention, reservation being made to make such changes in any of the essential, and all of the non-essential details as may come within the purview of the accompanying claims.

What I claim as my invention is 1. In a steering mechanism, the combination with an axle having steering knuckles adjacent the ends thereof, of a shaft supported by said axle intermediate the ends thereof and extending transversely of the same, bell crank levers mounted upon said shaft, links establishing a connect-ion between one arm of said levers and the knuckles aforesaid, and a driving member connected to the other arm of said bell crank levers for actuating the same to effect an operation of said steering knuckles.

2. In a. steering mechanism, the combination with an axle having steering knuckles adjacent the ends thereof, of a shaft supported by said axle intermediate the ends thereof and extending transversely of the same, a pair of levers ournalled intermediate the ends thereof upon said shaft, links establishing a connection between one end of said levers and the knuckles aforesaid, and a driving member journalled upon said axle extending between and connected to the opposite ends of said levers for actuating the same to effect an operation of said steering knuckles.

3. In a steering mechanism, the co1nbination with an axle having steering knuckles adjacent the ends thereof, of a rotatable worm member journalled upon said axle intermediate the ends thereof and extending rearwardly therefrom, a shaft also journalled upon said axle and extending transversely of said rotatable screw adjacent thereto, a pair of spaced levers mounted upon said shaft intermediate the ends thereof, links connecting one end of said levers to the steering knuckles, and means upon the opposite ends of said levers engageable with opposite sides of said screw to be actuated by the latter.

In testimony whereof I aflix my signature.

EAR-LE S. MAGPHERSON. 

